WAN FailOver and WAN_DHCP

[The_Sage]

Hi guys, I have set up a OPNSense box with 3 NIC's. Firmware is 18.7.1
Interfaces LAN, WAN and OPT1, OPT1 is used as a 4G Failover with a 4G router (which works pluged into a pc)

I set WAN as Static IP to the internet. As per OPNSense Multi WAN documentation. 

To cut a long story short, This setup works as expected (better than expected, with switch overs withe 20 seconds.) My problem arises when I  change the WAN over to DHCP setting, reconfigyre DNS, gateways, Gateway groups Etc As per OPNSense Multi WAN documentation. I reboot OPNSense and the WAN sometimes comes up and works as expected. If I pull the WAN plug, or the WAN doesnt come up, it stays in a state PENDING. After a few restarts, it may work through the WAN but more often than not, remains in the PENDING state.

If I reconfigure the WAN to be STATIC everything works OK, so I dont think it is in the set up as I have switched from DHCP to Static at least 5 times and each time STATIC works perfectly.

Can anyone shed some light? Will more config info be helpful?
What am I missing?


The Stuck Sage

[The_Sage]

After more research, and testing, I can confirm that this post, https://forum.opnsense.org/index.php?topic=7199.0 by advcron is exactly what I can reproduce.